In International Patent WO 99/30877, the present inventor disclosed a high efficient gripper consisting of an extremely simple mechanism. Such gripper has a feature of transforming a slight amount of translation to an amount of bending displacement expanded tens times larger at a finger tip by applying a buckling phenomenon to the long columns of the fingers without using any special displacement expanding mechanism.
Such gripper can grip the minute part softly, and is suitable for robot hands, for smaller and lighter.
However, there was a problem that the gripper did not vary the amount of opening or closing the fingers and was limited in the size of a gripped object.